"Greg" wrote in message
...
Hi

I am trying to build a broadband UNUN 9:1 from 1.8 mhz to 30mhz. I
have had no luck.

The first one the that I built, I used #67 material
snip

The question is simply how do I build a broadband UNUN or
Autotransformer from 1.8mhz to 30mhz and what core do I use? I am
coming to the conclusion that these auto transformers or high
impedance UNUN's are narrow band devices?

I am playing around with a terminated T2FD type antenna trying
different impedances, 450,600,800 and 1000 ohms termination resistors.

Bob

Here are some papers that may help.
http://www.hep.princeton.edu/~mcdona..._4_1_46_05.pdf
http://standards.ieee.org/reading/ieee/ept/trans.pdf

These came from here, there are others.
http://unjobs.org/authors/jerry-sevick

Mike